LazyTools

🔒 Everything on LazyTools runs in your browser — your data is never uploaded to any server. How it works

Unit & Measurement Converters

Convert between metric, imperial and US units instantly. Every converter uses the exact internationally defined factors, shows you the formula, and runs entirely in your browser — nothing is uploaded, ever.

Browse by measurement

Most-used conversions

Frequently asked questions

Are these unit converters accurate?

Yes. Every conversion uses the exact, internationally agreed definition of each unit (for example, 1 inch = 25.4 mm exactly and 1 lb = 0.45359237 kg exactly). Results are computed to your chosen precision with no rounding surprises.

Is anything I type sent to a server?

No. All conversions run as JavaScript in your browser. LazyTools has no conversion server — the pages even work offline once loaded.

Why use this instead of asking an AI chatbot?

Speed and reliability: the converter gives an exact, deterministic answer instantly, shows the formula, and never miscalculates. Language models can make arithmetic mistakes and are slower for a simple conversion.